KR0180900B1 - Dry process system - Google Patents

Abstract

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Description

Dry Processing Equipment

1 is a schematic view showing an example of a conventional dry corrosion apparatus belonging to the type of dry processing apparatus.

2 is a schematic view showing another example of a conventional dry etching apparatus belonging to the type of dry processing apparatus.

3 is a schematic view showing a first embodiment of a dry processing apparatus according to the present invention.

4 is a schematic view showing a second embodiment of a dry processing apparatus according to the present invention.

5 is a schematic view showing a third embodiment of a dry processing apparatus according to the present invention.

6 is a schematic view showing a fourth embodiment of a dry processing apparatus according to the present invention.

7 is a schematic view showing a fifth embodiment of a dry processing apparatus according to the present invention.

8A is a schematic diagram of an electron transport process model in a plasma generated between opposing electrodes at wide intervals.

8b is a schematic diagram of an electron transport process model in a magnetron plasma generated between opposing electrodes at a narrow distance.

9 is a graphical representation of the emission spectrum of the magnetron plasma of CHF 3.

10 is a graphical representation of the gas pressure dependence of Hα emission intensity.

11 is a graphical representation of the self-biss voltage (V) in a device according to the invention and a conventional device versus corrosion rate (μm / min).

FIG. 12 is a graph showing the distribution of corrosion depth of a 6 inch silicon oxide (SiO) wafer corroded with rotating magnetic fields.

* Explanation of symbols for main parts of the drawings

1: reaction chamber 3: substrate

6: high frequency power source 7: blocking capacitor

9: insulator 10: electric field

11: magnetic field 12: 3 set solenoid

15: first DC power supply 16: first high frequency power supply

17: ideal phase 21: first electrode

22: second electrode 25: second DC power

27: power divider

The present invention relates to a dry processing apparatus using magnetron discharge used as a CVD (chemical vapor deposition) apparatus and a corrosion apparatus and a sputtering apparatus. The magnetron discharge which consists of the above electrodes, respectively, relates to the dry processing apparatus generate | occur | produced between adjacent electrodes. 1 is a schematic view showing an example of a conventional dry processing apparatus.

The conventional dry processing apparatus is composed of a reaction chamber 1 and a cathode electrode 2 provided at the bottom of the reaction chamber 1, and the electrode is insulated from the reaction chamber 1 by an insulator 9. .

The negative electrode 2 is connected to the terminal of the high frequency power source or the RF (Radio Frequency) power source 6 via the low voltage capacitor 7, and the other terminal of the high frequency power source and the reaction chamber 1 are grounded.

A pair of three solenoids 12 is provided outside the reaction chamber 1 to generate the magnetic field 11 in a direction substantially parallel to the surface of the cathode electrode 2.

The substrate or wafer 3 is disposed on the cathode electrode 2.

The reaction gas 4 is introduced into the reaction chamber 1 and the exhaust gas 5 is discharged from the reaction chamber 1.

A high frequency power Ph of 13.56MHZ is applied to the cathode electrode 2 via the support capacitor 7, and the reaction chamber 1 acts as the anode electrode 8.

A high frequency electric field 10 perpendicular to the surface of the cathode electrode 2 is generated on the cathode electrode 2 and a magnetic field parallel to the surface of the cathode electrode 2 is generated by the solenoid.

2 is a schematic view showing another example of a conventional dry corrosion apparatus.

In the conventional dry corrosion apparatus, the anode electrode 8 is disposed on the cathode electrode 2 at an interval of about 70 mm so that the anode electrode 8 is parallel to the cathode electrode 2 and the anode electrode 8 is grounded. Except for opposing 2), it has the same structure as the conventional apparatus described above.

The eagle conventional device operates as follows.

The water reaction chamber 1 in which the substrate 3 to be corroded is disposed on the cathode electrode 20 is sufficiently exhausted by the vacuum pump, and the reaction gas 4 is brought into the reaction chamber 1 such that the gas pressure is about 10 mTorr. Is introduced.

After that, the high frequency power ph is supplied to the cathode electrode 2 from the high frequency power via the stop storage impingement 7, whereby the reaction gas is excited into a plasma phase composed of positive and negative electrons.

The high frequency electric field 10 is generated in a direction perpendicular to the surface of the negative electrode 2 by supplying high frequency power to the negative electrode. At the same time, the magnetic field 11 is formed in a direction parallel to the surface of the cathode electrode 2 by a pair of three solenoids.

In the intersecting high frequency electric field 10 and the magnetic field 11 formed in the space on the substrate, light electrons in the form of a spiral in a direction perpendicular to the magnetic field lines and a small diameter orbit cause a spiral circular motion. Electrons that collide violently with the neutral corrosive gas generate a high density plasma, so that a magnetron discharge 13 is generated.

Since the electrons in the magnetic field move in a direction perpendicular to the magnetic field by the force of Lorenz, the plasma density is biased to one side.

In order to prevent this, a pair of three solenoids are provided around the reaction chamber 1, and an alternating current flows through the three pairs of solenoids, so that the distribution of the plasma density is averaged and a uniform magnetic field is generated.

In general, the ionization rate of the reaction gas due to high frequency electric discharge excitation is about 10 ^−- . However, the corrosion rate by magnetron discharge due to ionization rate or size of the two units to 10 ^²2 than the ionization rate of the magnetron discharge is ahead in significantly more than one unit.

However, in the above-described apparatus, when the magnetic field is not rotated, a distribution in which the plasma density distribution is biased to one side is formed, so that uniform corrosion is difficult.

That is, the variation in corrosion uniformity was large and the variation ratio was more than ± 30%.

In addition, since the magnetic bias voltage of the cathode electrode 2 is significantly different from the magnetic bias voltage of the anode electrode 8, at least two substrates disposed on both the cathode electrode 2 and the anode electrode 8 are corroded. It was impossible to let.

It has also been considered that it is more impossible to have three or more electrodes in the reaction chamber, to arrange the substrates on each electrode and to corrode the substrates with good uniformity at the same time.

Therefore, it is one object of the present invention to provide a dry processing apparatus in which a plurality of electrodes are provided at regular intervals in a reaction chamber, and a plurality of substrates disposed on each electrode can be processed simultaneously with high quality uniformity. .

The above-mentioned object is to provide three or more electrodes connected to each alternating current power source through a reaction chamber and a stop capacitor having an inlet of a reaction gas and an outlet of exhaust gas, and one or a plurality of electrodes for generating a magnetic field almost parallel to the surface of each electrode. The distance between the magnetic field applying means and the adjacent electrode can be achieved by a dry processing apparatus configured to be set to such an extent that electrons can move almost without colliding in the space of the adjacent electrode acid.

In addition, the above object of the present invention is to provide a reaction chamber having an inlet of a reaction gas and an outlet of exhaust gas, three or more electrodes each connected to an AC power source through a power distribution device, and a magnetic field almost parallel to the surface of each electrode. The distance between one or a plurality of magnetic field applying means for generating and adjacent electrodes can also be achieved by a dry processing apparatus configured by setting the space between adjacent electrodes to such an extent that electrons can move with little collision.

In addition, the object of the present invention described above is that the reaction chamber having an inlet of the reaction gas and an outlet of the exhaust gas and the reaction chamber are connected to the anode side of the DC power supply and grounded, and at least three electrodes are connected to the cathode side of the mainstream power supply. And one or a plurality of magnetic field applying means for generating a magnetic field substantially parallel to the surface of each electrode. The distance between adjacent electrodes can also be achieved by a dry processing apparatus configured by setting the extent that electrons can move in the space between adjacent electrodes with almost no adjacent collision.

In the present invention, the distance between adjacent electrodes is preferably 1-5 cm.

In the present invention, the internal pressure of the reaction chamber is about 1-100 m Torr, preferably 1-10 m Torr.

In addition, the magnetic field strength of the present invention is about 50-500gauss.

Each electrode in the present invention preferably has the same area with each other, and each distance between adjacent electrodes is preferably the same with each other.

In the present invention, when an AC power source is used as the power source of the dry processing apparatus, the AC power source may be provided for supplying synchronous AC power having the same frequency to each electrode via a stop capacitor with an appropriate phase difference.

In addition, the AC power supply may be provided to supply synchronous AC power when the reaction chamber is grounded with the same frequency through the stop capacitor in substantially the same phase for each electrode.

In this case, the electrodes of the first group and the electrodes of the second group may be electrically connected to each other.

In the present invention, one set of the first alternating current power supply and the second alternating current power supply can be used as an alternating current power supply of the dry processing apparatus, and the first alternating current power supply is connected to the second alternating current power supply via an ideal phase device.

The phase difference in the present invention is in the range of 0 ° ± 40 ° or 180 ° ± 40 °.

In the present invention, if a gas is used for film formation such as SiH, the dry treatment apparatus according to the present invention can be used as a CVD apparatus.

If a corrosive gas such as CF is used, this device can be used as a corrosive device.

Also, if a sputtering gas such as Ar is used, the device can be used as a sputtering device.

According to the present invention, a magnetron discharge occurs because an electric field and a magnetic field cross each other, and the magnetron discharge generates a plasma.

Some of the light weight electrons present in the plasma are transferred to each electrode and stored in the stop capacitor, whereby a negative bias DC voltage is formed.

The formation of the magnetic bias voltage results in the formation of ion sheaths with high cation concentration near each electrode.

However, the electric resistance of the ion seeds is increased by the very low mobility of the cations, so that a strong electric field is applied to each electrode in the direction perpendicular to each other.

The electric field corresponding to the magnetic bias voltage formed in the ion sheath of each electrode moves toward each electrode.

The electric field line corresponding to the magnetic bias voltage formed in the ion sheath of the first electrode is the opposite direction to the electric field line corresponding to the magnetic bias voltage formed in the ion sheath of the second electrode opposite to the first electrode.

Since the magnetic fields are in the same direction and one electric field corresponding to the first electrode and the other electric field corresponding to the second electrode are opposite to each other, the directions of the Lorentz forces acting on the secondary electrons emitted from each electrode are opposite to each other. do.

If the distance between adjacent electrodes is set so that the electrons can move in the space between adjacent electrodes with little collision (i.e., average free stroke of electrons), they will occur near one plasma and another electrode generated near one electrode. The different plasmas can be mixed together so that the distribution of the mixed plasmas is almost the same everywhere. Therefore, a substantially uniform plasma can be formed without rotating a magnetic field.

In addition, when the distance between adjacent electrodes is set to be substantially equal to the electron rotation diameter (ie, twice the radius of the lamus), since the ion seeds are formed on the surface of each electrode, each electron moves into the ion seeds, and The electrons moved into the sheath are repelled by the strong electric field of the ion sheath and return in the opposite direction.

Thus, there is a high probability that the rotating electrons will continue to rotate until they collide with the gas molecules without greatly shifting to sinners in space.

When the electrons are the pressure of the reaction gas corresponding to the pressure that can move almost without collision, the electrons freely rotate about one revolution before they collide with the gas molecules.

The gas pressure is inversely proportional to the mean free path of the electrons.

Therefore, to rotate the electrons more than one rotation, it is necessary to limit the pressure to be less than or equal to the above-mentioned pressure.

That is, if the distance between adjacent electrodes is set to be less than or equal to the area of the electron where the electrons can move almost without collision, the electrons may be between adjacent electrodes until the electrons collide with gas molecules in the space to produce a uniform plasma. You can continue to move from side to side almost without floating.

In addition, since the movement of the electrons in the left and right directions is small, plasma having high quality uniformity is generated. Since the ionization rate of the plasma by the magnetron discharge is 2 units or more higher than the plasma generated by the general high frequency discharge, the dry corrosion according to the present invention can be performed at a speed higher than that of the conventional apparatus.

EXAMPLE

Hereinafter, the present invention will be described by way of example with reference to the drawings.

3 is a schematic view showing a first embodiment of a dry processing apparatus according to the present invention, in which FIG. 3 shows a conventional apparatus indicating the same or corresponding part as that of the conventional apparatus shown in FIG. 1 and FIG. The same code | symbol as the relevant code | symbol of 2 degree is attached | subjected.

The first embodiment of the present invention is composed of two first electrodes 21 and two second electrodes 22 arranged alternately in parallel in the reaction chamber 1.

The first electrode 21 is connected to one terminal of an alternating current, a high frequency or a high frequency power supply 6 via the stop capacitor 7, and the second electrode 22 is a high frequency power source 6 via the stop capacitor 7. Is connected to the other terminal.

In order to make the plasma generated between the adjacent electrodes 21 and 22 uniform, the capacitance of the blocking capacitor 7 for the first electrode and the capacitance of the stopping capacitor for the second electrode are substantially equal to each other. For this reason, it is preferable that the distance between adjacent electrodes is the same value, and that the area of each electrode is almost the same.

A first electrode 21 connected to one terminal of the high frequency power supply 6 via the stop capacitor 7 and a second wire connected to the other terminal (6) of the high frequency power supply via the stop charger 7; The two electrodes 22 are insulated from the reaction chamber 1 by insulators 9 and 9, respectively.

The pair of triad solenoids 12 have the first and second electrodes 21 and 22 in a direction in which the magnetic field lines 11 are parallel to the first and second electrodes 21 and 22. It is arrange | positioned at the exterior of the reaction chamber 1 so that the space may be enclosed.

In the first embodiment, in order to stabilize the plasma discharge, the reaction chamber 1 is grounded and the average voltage of the two terminals of the high frequency power supply 6 is set to OV.

However, it is not necessary to always ground the reaction chamber 10, it is preferable that the reaction chamber 1 is not grounded and one terminal of the high frequency power supply 6 is grounded.

When one terminal of the high frequency power supply 6 is grounded, the reaction chamber 1 is preferably in an electrically floating state.

In addition, the dry processing apparatus in the first embodiment is provided with one high frequency power supply.

However, it is also possible to use two high frequency power sources whose frequencies, which are mutually opposite phases, in which high frequency power supplies are controlled to output the same power, are synchronized with a phase difference of 180 degrees.

However, when two high frequency power supplies are used, the same action and effect can be obtained by supplying high frequency power to each electrode 21 and 22 from each high frequency power supply via each of the stop chargers 7 and 7.

In this case, one electrical energy supplied to the first electrode and the other electrical energy supplied to the second electrode can be changed, and the phase difference between the power supplied to the first electrode and the power supplied to the second electrode can be changed. Can be.

Further, the positive electrode 21 can be adjusted by appropriately adjusting the ratio of the phase difference between the electric energy supplied to the first electrode, the electric energy supplied to the second electrode, the amount of power supplied to the first electrode, and the amount of power supplied to the second electrode. 22) It is possible to optimize the distribution of the plasma generated between.

The solenoid 12 for applying a magnetic field may also be replaced with other means for applying a magnetic field, for example, a combined rod-shaped permanent magnet.

Any means for applying the magnetic field 11 to the substrate 3 parallel to the substrate 3 on the electrodes 21 and 22 can be used.

Even if the magnetic field is stopped, sufficient uniformity of plasma density can be obtained.

However, if the magnet rotates, it is averaged again to improve uniformity.

The substrate 3 is disposed on the electrodes 21 and 22, respectively.

However, it is not necessary to arrange the board | substrate 3 on both electrodes 21 and 22, and it is necessary to arrange only in either the electrode 21 or the electrode 22. As shown in FIG.

Since the first electrode 21 and the second electrode 22 are preferably as symmetrical to each other as possible, both electrodes should be parallel to each other, and a stop shaft 7 for the second electrode 22 of the first electrode 21 is provided. ) Needs to be as close to 1: 1 as possible.

In this case, it is preferable that the ratio of the areas of the stopping capacitor 7 and the second electrode 22 for the first electrode has the same capacitance as much as possible.

In the first embodiment, the substrate 30 is disposed on the first electrode 21 and the second electrode 22.

After the reaction chamber 1 is sufficiently evacuated by the vacuum pump, the reaction gas 4 is supplied to the reaction chamber 1 such that the internal pressure of the reaction chamber 1 becomes about 1-100 mTorr or less and the internal pressure of the reaction chamber is adjusted. Is introduced into.

An electric current flows through the solenoid 12 and then a magnetic field 11 of about 50-500gauss is placed in the space between the positive electrodes 21 and 22 so that the magnetic field 11 acts in parallel with each electrode 21, 22. It is human to the board | substrate 3.

When the power Rh of the high frequency power supply 6 is supplied to the first electrode 21 and the second electrode 22 in the opposite phase through the stop capacitors 7 and 7, respectively, by the supplied power Ph, An electric field 10 is generated in the substrate 3.

Magnetron discharge occurs because the electric field 10 and the magnetic field 11 cross at right angles.

Plasma is generated by the magnetron discharge, and the light electrons of a part of the plasma move to the first electrode 21 and the second electrode 22, are stored in the stop capacitor 7, and generate a self bias voltage. .

Ion seeds having a high cation density are generated in the vicinity of the first electrode 21 and the second electrode 22 by the generation of a negative direct current magnetic bias voltage.

The direction of the electric field line 10 corresponding to the magnetic bias voltage generated in the ion seeds of the first electrode 21 and the second electrode 22 is directed upward and downward, respectively. Since the directions of the magnetic field lines 11 are the same and the directions of the electric field lines 10 are opposite to each other, the direction of the force of Lorenz acting on the secondary electrons emitted from the electrodes 21 and 22. Are in opposite directions.

That is, near the first electrode 21, the plasma density is high at the portion corresponding to the back side (that is, the opposite side) of the ground drawn in the drawing, and is low at the portion corresponding to the front side (this) of the ground drawn in the drawing.

Near the second electrode on the other side, the plasma density is low at the portion corresponding to the back side (that is, the opposite side) of the ground drawn in the drawing, and high at the portion corresponding to the front side (this) of the ground drawn in the drawing.

If the distance between the first electrode 21 and the second electrode 22 is sufficiently short that the space between the first electrode 21 and the second electrode 22 is such that electrons can move almost without collision, the first electrode ( 21) One plasma generated near the other and the other plasma generated near the second electrode 22 are mixed without being separated from each other, and the distribution of the plasma density becomes almost uniform.

Therefore, the plasma can be generated almost uniformly without rotating the magnetic field.

Of course, the uniformity of the plasma can be further improved if the magnetic field is rotated.

The distance between the positive electrodes 21 and 22 is preferably about 1 cm to 5 cm.

The ionization rate of the plasma generated by the magnetron discharge is 2 units or more higher than the ionization rate of the plasma generated by the general high frequency discharge.

Therefore, as the apparatus of the first embodiment, dry corrosion can be performed at a speed higher than one unit compared with the conventional apparatus.

If a gas for film formation such as SiH is used in this apparatus, this apparatus can be used as a CVD apparatus.

If a corrosive gas such as CF is used, the device may be used as a corrosive device.

Also, if a sputtering gas such as Ar is used, this device can be used as the sputtering device.

The apparatus of the first embodiment can process six months of the substrate 3 simultaneously.

In addition, by using the dry processing apparatus, at least two substrates 3 are disposed on each electrode 21, 22, and at least 12 substrates 3 can be processed at the same time.

In addition, the total number of first electrodes and the total number of second electrodes may be 3 or 5 or more, respectively. In this case, the first electrode 21 and the second electrode 22 need to be alternately arranged. As described above, the first electrode 21 and the second electrode 22 are preferably parallel to each other.

However, the electrodes 21 and 22 do not always have to be flat, but may be curved.

FIG. 4 is a schematic view showing a second embodiment of the dry processing apparatus according to the present invention, and the same reference numerals as in FIG. 3 refer to the same or corresponding parts as the apparatus shown in FIG.

The second embodiment is composed of two first electrodes 21 and two second electrodes 22, and the first electrode 21 and the second electrode 22 are electrically connected to each other so that they have the same potential. The high frequency power Ph is supplied from the high frequency power supply 6 to the electrodes 21 and 22 synchronously in the same phase from the high frequency power supply 6, and the reaction chamber 1 is grounded. have.

The high frequency power supply 6 may be replaced by two high frequency power supplies which are synchronized in the same phase and controlled to have the same power, thereby obtaining similar operation and effects which can be obtained using one high frequency power supply.

In this case, the electrical energy and the phase difference of the power supplied from the two high frequency power sources to the first and second electrodes through the stop capacitor may be different from each other.

Therefore, the distribution of plasma generated between the positive electrodes 21 and 22 is characterized by the electrical energy of the power supplied to the first electrode, the electrical energy of the power supplied to the second electrode, the amount of power supplied to the first electrode, and the second. It can be optimized by appropriately adjusting the ratio of the phase difference with the amount of power supplied to the electrode.

In addition, it is preferable that the reaction chamber is grounded if one terminal of each high frequency power supply is grounded.

The magnetic field 11 is applied in parallel to each electrode 21, 22 by the solenoid 12 as in the first embodiment.

In order to improve the uniformity of the plasma and generate a high density plasma, the distance between the first electrode 21 and the second electrode 22 is preferably less than about 1 cm to 5 cm.

Such a distance allows electrons to move almost without collision in the space between the first electrode 21 and the second electrode 22.

The first electrode 21 and the second electrode 22 are conductive wires in the reaction chamber 1 so as to have the same effect as the first and second electrodes are electrically connected to each other outside the reaction chamber. It can be electrically interconnected with a conductor plate.

In the first embodiment, a high frequency power source 6 is used as the power source.

However, in this embodiment, the high frequency power source 6 can be replaced with a direct current power source.

If DC power is used as the power source, the support capacitor 7 is unnecessary.

A negative voltage is applied directly to each electrode 21, 22, a positive voltage is applied directly to the reaction chamber 1, or another electrode is arranged in the reaction chamber.

One substrate 3 or a plurality of substrates 3 may be disposed on the positive electrode 21, 22 or on the electrode 21 or 22.

In the second embodiment, a film forming gas such as SiH was used in the same manner as the apparatus of the first embodiment. This apparatus can be used as a CVD apparatus, and if a corrosive gas such as CF is used, the apparatus can then be used as a corrosion apparatus.

Also, if a sputtering gas such as Ar is used, the device can be used as a sputtering device.

Also, the conditions for generating the plasma are almost the same as those given in the first embodiment.

In the second embodiment, three or more electrodes can be used in the same manner as in the first embodiment, wherein the area of each electrode is almost similar to each other, and the respective distances between adjacent electrodes are almost similar to each other, and each The electrodes are preferably parallel to each other, and the electrodes 21 and 22 are preferably electrically connected to have the same potential.

In this case, four or more substrates can be arranged on opposite surfaces of adjacent electrodes.

In the first and second embodiments, a high frequency power source is used as a power source for generating plasma.

However, a low frequency power source can also be used as a power source for generating plasma.

5 is a schematic diagram showing a third embodiment of a dry processing apparatus according to the present invention, and the same reference numerals as those in FIG. did.

The third embodiment is composed of two first electrodes 21 and two second electrodes 22, which are alternately arranged in parallel in the reaction chamber 1.

In the third embodiment, the apparatus is provided with high frequency power sources 26 and 16 to independently supply high frequency power Ph2 and Ph1 as high frequency power sources.

The first high frequency power source 16 and the second high frequency power source 26 are connected to each other via the phase shifter 17.

The pair of high frequency power sources 26 and 16 is controlled by the phase shifter 17 to oscillate at the same frequency with an arbitrary phase difference.

The high frequency power Ph1 Ph2 is independently controllable.

The first electrode 21 is connected to one terminal of the second high frequency power source 26, and the second electrode 22 is connected to one terminal of the first alternating current or the high frequency power source 16, respectively. The other terminals of the harmonics power supply are grounded.

In order to make the state of the plasma generated in the space between the adjacent electrodes the same, the distances between the adjacent electrodes are equal to each other, and the areas of the respective electrodes 21 and 22 are substantially equal to each other, and the first and second are the same. It is preferable that the capacities of the stopper chargers 7 and 7 for the electrodes of are substantially the same.

The solenoid 12 can also be replaced by other means for applying a magnetic field between adjacent electrodes, such as a permanent magnet coupled to one of the rods, for example.

Any means for applying a magnetic field that is substantially parallel to the substrate 3 on the electrodes 22 and 22 can be used.

Even when the magnetic field is stopped, sufficient uniformity of the plasma density can be obtained.

However, if the magnetic field is rotated, the plasma density is also more uniform so that the uniformity of the plasma density is improved.

In the third embodiment, the keypad 3 is disposed on the electrodes 21 and 22, respectively.

The reaction chamber 1 is sufficiently evacuated, and then the reaction gas 4 is introduced into the reaction chamber 1 such that the internal pressure of the reaction chamber 1 becomes about 1-100 mTorr or less.

A magnetic field 11 of about 50-500gauss is applied to the space between adjacent electrodes 21 and 22 so that current flows through the solenoid 12 and the magnetic field lines are applied almost parallel to each electrode 21 and 22. do.

Through the stop capacitor 7, power Phh and Ph2 of the high frequency power source 16 and 26 are supplied to the respective electrodes 21 and 22 at an arbitrary phase difference and an arbitrary power supply ratio. An electric field is generated on the substrate 3 by the power Ph1 Ph2.

The direction of the electric field changes according to the phase difference between the powers Ph1 and Ph2 and the power supply ratio.

Since the electric field 10 and the magnetic field 11 cross each other at right angles, a magnetron discharge is generated, and a plasma is generated by the magnetron discharge, and some of the lighter electrons in the plasma are the first electrode 21 and the second electrode. It moves to 22 and is stored in the stop capacitor 7 to generate a negative magnetic bias voltage.

The generation of a negative magnetic bias voltage causes ion seeds having a high cation density near the first electrode 21 and the second electrode 22.

In the ion sheath portion there are cations with high density.

However, since the mobility of the cations is remarkably low, the electrical resistance of the ion-seed portion becomes high so that strong application can be made in the direction perpendicular to the respective electrodes 21 and 22.

The direction of the electric field corresponding to the self bias voltage generated in the ion-seed portions of the first and second electrodes 21 and 22 is directed toward the respective electrodes 21 and 22, i.e. Downwards, faced.

The cations are accelerated by the electric field, and the accelerated cations collide with the first and second electrodes 21 and 22 to generate secondary electrons.

In such a state, when the distance between the adjacent electrodes 21 and 22 is changed, a difference occurs when the distance between adjacent electrodes is wide and when the distance between both electrodes is narrow.

This apparatus can process six substrates 3 simultaneously.

In addition, by using this dry processing apparatus in which two or more substrates 3 are disposed on each electrode 21, 22, 12 or more substrates 3 can be processed simultaneously.

In addition, the total amount of the electrode 21 and the total amount of the electrode 22 may be 3 or 5 or more, respectively, wherein the first electrode 21 and the second electrode 22 should be alternately arranged, and the first electrode ( 21 and the second electrode 22 are preferably parallel to each other.

However, the electrodes 21 and 22 do not necessarily have to be flat, but may be curved.

FIG. 8A shows the motion of electrons in the plasma when the distance between the first electrode and the second electrodes 21 and 22 is wide, for example, from 60 mm to 100 mm.

Since the distance between adjacent electrodes is large enough, the secondary electrons emitted from each of the electrodes 21 and 22 are moved left and right by the action of the perpendicularly intersecting electric and magnetic fields. Such a movement is a circular movement.

Secondary electrons emitted from the first electrode 21 move to the right, and secondary electrons emitted from the second electrode 22 move to the left.

In addition, if the first electrode 21 and the second electrode 22 are wider than the electron region that can move almost without collision in the space between the electrodes 21, 22, the first electrode 21 is emitted from the primary electrode 21. The secondary electrons and the secondary electrons emitted from the secondary electrode 22 are separated from each other so that plasma is produced separately in the vicinity of the primary electrode 21 and in the vicinity of the secondary electrode 22.

However, if the first electrode 21 and the second electrode 22 are substantially the same as the electron region that can move almost without collision in the space between each electrode 21, 22, that is, it is the average free stroke of the electrons. The plasma generated around the electrodes is mixed with each other so that the distribution of the mixed plasma is the same everywhere.

The average free stroke of electrons is the average distance of electrons that can move in the gas molecules until they collide with the gas molecules.

Here, the average free stroke of the electron λe is as follows.

here, [

λc = λg × 5.6 (average free stroke of λg0 gas)

h = viscosity

p = density

u = speed

m = molecular weight of gas]

On the other hand, in FIG. 8B, electrons in the plasma when the distance between the first electrode 21 and the second electrode 22 are substantially equal to the Larmor's change (diameter) twice as large as the electrons. Indicate the movement of

That is, when the magnetic flux density and the magnetic bias voltage of the magnetic field are 150 gauss and 200 V, respectively, the radius of rotation of the electron, that is, the radius of the lammers, is about 4 mm.

Then the diameter of rotation of the secondary electrons with respect to the magnetic field lines is about 8 mm.

The secondary electrons, rotating about the magnetic field of force about 8 mm in diameter, approach the opposite electrode.

Since the ions are formed on the surface of the electrode, the electrons are repelled by the strong negative electric field and return to the opposite direction.

Therefore, when the distance between adjacent electrodes is narrow, rotation will continue, without moving an electron large left and right until rotating electrons collide with a gas molecule.

The circumference of a circle of about 8 mm diameter is about 25 mm. The gas pressure at which the average free stroke of the former reaches 25 mm is about 10 mTorr, which is slightly different depending on the type of gas.

Therefore, in the above-mentioned plasma generation state, the electrons rotate freely over about one revolution until the electrons collide with the gas molecules in the gas having a pressure of 10 mTorr.

Since the average free stroke length of electrons is inversely proportional to the gas pressure, it is necessary to keep the gas pressure below about 10 mTorr to enable the electrons to rotate more than one revolution.

That is, when the distance between adjacent electrodes is about 10 mm to 30 mm and the gas pressure is about 10 mTorr or less, the electrons continue to rotate without substantially moving the space between the adjacent electrodes 21 and 22 to the left and right. It collides with gas molecules in the space to generate ions or radicals of plasma.

That is, since the movement in the left and right directions of the electrons in FIG. 8 (b) is small, the electrons emitted from the electrodes 21 and 22 of each d are spaced around the magnetic field lines between the adjacent electrodes 21 and 22. Continue to rotate along and effectively collide with the gas molecules so that a plasma with better uniformity is generated.

Therefore, as shown in Figs. 8A and 8B, if the distance between each electrode 21 and 22 is substantially less than or equal to the average free running information of electrons, the plasma between each electrode 21 and 22 is The uniformity of is improved without the need to rotate the magnetic field, and of course is further improved by rotating the magnetic field.

Moreover, the density of the plasma is also increased, which is effective in corrosive or CVD devices.

FIG. 9 shows the emission spectrum of the CHF gas at a pressure of 1 Pa by the apparatus according to the third embodiment, and the luminance line spectrum of wavelength 656.3 nm is the α-line spectrum of hydrogen. (Hα).

The intensity of the Hα-ray represents the emission intensity of hydrogen atoms generated by the decomposition of CHF, and the degree of decomposition of CHF, that is, the density of plasma.

Fortunately, there is little noise light around the Hα-line, so the plasma density can be compared as a comparison of the Hα-ray intensity.

FIG. 10 shows the dependence of the radiation intensity of Hα rays when CHF gas is introduced into the apparatus and the gas pressure is changed to 0.4-10Pα according to the third embodiment.

As shown in FIG. 10, even if the gas pressure was lowered from 10 Pa to 0.4 Pa, the Hα radiation intensity was hardly changed.

In addition, lowering the gas pressure from 10 Pa to 0.4 Pa makes the interior of the reaction chamber thinner by about 40 times in terms of gas molecular density, but there is no change in the plasma density emitted.

That is, the generation efficiency of the plasma increases as the gas pressure is lowered to about 1 Pa or less.

There is a relation between the phase difference between the power PH2 and the power Ph1 and the uniformity of the plasma.

In the phase difference within the range of 0 DEG to 0 ± 40 DEG, the plasma uniformity is very good and the plasma is almost uniform, and it can be observed visually.

When the state of the plasma and the magnetic field 11 are stopped, a good corrosion uniformity of about ± 15 ° can be obtained.

On the contrary, when the state of the plasma and the magnetic field 11 are rotated, a very good uniformity of about ± 3% can be obtained.

When the phase difference is set within the range of about 180 ° ± 40 °, the uniformity of the plasma is slightly lowered, and the first and second electrodes 21 (both strings are arranged side by side in the direction perpendicular to the magnetic force line 11) ( On both strings of the space between the two, a slightly stronger plasma emission can be seen.

This light emission is corroded at a slightly higher rate of corrosion than the corrosion rate of the substrate of the other part of the substrate 3 near the strong plasma.

Thus, the uniformity of corrosion over the entire part of the substrate is worse than the case where the phase difference range is 0 ° ± 40 °.

By fixing such a state and the magnetic field, a corrosion uniformity of about ± 30% of the substrate can be obtained.

When the state of the same plasma and the magnetic field 11 are rotated, a very good corrosion uniformity of ± 3% can be obtained.

Within the phase difference range except the above-described phase difference and range, an intermediate uniformity is obtained between the uniformity of the plasma obtained by the phase difference near 0 ° and the uniformity of the plasma obtained by the phase difference near 180 °.

There is no close relationship between the plasma density and the phase difference.

In either phase difference, a darker plasma is generated than a normal magnetron plasma.

As a result, the substrate can be corroded at higher speed than any magnetron plasma in any phase difference. When an insulating dielectric plate is inserted between the first electrode 21 or the second electrode 22 and the substrate 3 disposed on the first electrode 21 or the second electrode 22, the first electrode Phase difference may occur between the high frequency power of the 21 or the second electrode 22 and the substrate 3 in the high frequency power.

In this case, the phase difference between the high frequency power Ph1 and the Ph2 is defined as the phase difference between the high frequency power Ph1 applied on the substrate 3 and the high frequency power Ph2 applied to the substrate 3. It is desirable to consider.

The uniformity of the plasma is sensitively affected by the high frequency power supply rate of the power ph2 supplied to the first electrode 1 and the power Ph1 supplied to the second electrode 22.

When the power supplied to each electrode 21 or 22 and the power supplied to both electrodes 21 and 22 are made large enough, a dark plasma will generate | occur | produce.

In this case, if the first electrode or the second electrode is grounded, and power is not supplied to either of the first electrode or the second electrode, an extremely non-uniform plasma is generated and the plasma density is greatly reduced.

For example, if the power Ph2 supplied to the first electrode 21 is sufficiently large, while the power Phh supplied to the second electrode is slightly smaller, the space between the first and second electrodes 21 and 22 is reduced. High density plasma is generated.

The self bias voltage of the first electrode 21 becomes high, the ion seeds become thick, and the kinetic energy of the cations incident on the substrate 3 also increases.

On the contrary, the magnetic bias voltage of the second electrode 22 decreases, the ion seed becomes thin, and the kinetic energy of the cations incident on the substrate 3 decreases.

Therefore, such a device can be suitably used for plasma processing such that the first electrode 21 corrodes or sputters the substrate 3 at high speed with large ion energy, while the second electrode 22 is slightly high speed with less ion energy. Furthermore, it can be suitably used to reduce the collision damage of ions and to corrode or to perform plasma treatment such as CVD.

When the power Ph2 supplied to the first electrode 21 and the power Ph1 supplied to the second electrode are equal to each other, the substrate 3 on the first electrode and the second electrode 21 and 22 is almost equal. Under conditions, it can be suitably used for performing plasma treatment such as CVD treatment and corrosion treatment.

Therefore, the ratio of power supplied to one of the first electrode 21 or the second electrode 22 is about 20% to 80% of the total power supplied to both the first and second electrodes 21 and 22. When the high density plasma is generated compared to the normal magnetron plasma.

Adjacent first and second electrodes 21 and 22 such that electrons can rotate between the first and second electrodes 21 and 22 and can rotate around the magnetic lines of force with little collision. If the distance between them is sufficiently narrow, the electrons emitted from the first and second electrodes 21 and 22 may continue to rotate while being properly mixed in the space between the first and second electrodes 21 and 22.

Therefore, a plasma having a denser density than a general magnetron plasma is generated and becomes almost uniform.

Therefore, it is possible to form an almost uniform plasma without rotating the magnetic field.

Of course, the uniformity of the plasma is further improved by rotating the magnetic field.

The ionization rate of the plasma by the magnetron discharge is two units or more higher than the ionization rate of the plasma by the general high frequency discharge.

Therefore, as the apparatus of the third embodiment, drying corrosion can be performed at one or more units at a higher speed than the conventional apparatus.

If a film forming gas such as SiH is used in this device, the device can be used as a CVD device.

If a corrosive gas such as CF is used, the device can be used as a corrosive device.

Also, if a sputtering gas such as Ar is used, this device can be used as a sputtering device.

FIG. 6 is a schematic view showing a fourth embodiment of the dry processing apparatus according to the present invention, with the same reference numerals as those shown in FIG. 5 indicating the same or corresponding parts as those shown in FIG. did.

The fourth embodiment consists of two first electrodes 21 and two second electrodes and is arranged in parallel to each other in a grounded reaction chamber.

The first and second electrodes pass through the high frequency power supply 6 and the power divider 27.

The other terminal of the high frequency power supply 6 is grounded.

In order to equalize the state of the plasma generated in the spaces between the adjacent electrodes, the distances between the adjacent electrodes are equal to each other, the areas of the electrodes 21 and 22 are equal to each other, and the first electrode and the second electrode are separated. It is preferable that the stop capacitors built in the output device of the power divider are identical to each other.

The power divider 27 is composed of a transformer for power distribution of a one input to two output type, a phase adjuster composed of a coil and a variable capacitor, and a matching box for matching the impedance of the first electrode to the impedance of the second electrode. .

The stop capacitor 7 is also built in the output terminal in the matching box.

There are several types of combinations, including the number of transformers and phase regulator matched multiples for power distribution, how to connect them, and the order in which they are connected.

However, any device that can arbitrarily adjust the power ratio and phase difference for an input can be regarded as equivalent to the power divider described above.

In power distributors, not all transformers, phase adjusters and matching boxes are required to distribute power.

For example, the same effect can be achieved by simply branching the output from one matchbox to two outputs.

In this case, however, it is not easy to adjust the power distribution ratio and the phase difference, and it is not easy to optimize the plasma generation conditions. However, the device is suitable for low-cost devices because it is relatively simple and consists of fewer parts.

The power divider 27 may distribute the high frequency power Ph of the high frequency power supply 6 to the first and second powers Ph1 and Ph2 having an arbitrary power ratio and phase difference, respectively, and these are the second electrodes. 22 and the first electrode 21 can be supplied.

In such a method, the same operation as in the case of using two high frequency power sources 16 and 26 as one high frequency power source 6 is possible.

The method of use, operation sequence and operation state are almost the same as those of the dry treatment apparatus of FIG.

In the third and fourth embodiments, a high frequency power source is used as a power source for generating plasma.

However, high frequency power can be replaced by low frequency power.

FIG. 7 is a diagram showing a fifth embodiment of the present invention, in which the same reference numerals as those in FIG. 5 denote the same parts of the apparatus shown in FIG. 5 or indicate corresponding parts.

In the fifth embodiment, it is composed of two first electrodes 21 and two second electrodes 22 and is arranged in parallel in the reaction chamber 1 alternately.

The first electrode 21 is connected to the negative electrode terminal of the second direct current power supply 25, and the second electrode 22 is connected to the negative electrode terminal of the first DC power supply 15. The positive terminal of the DC power supply 15, 25 is connected or grounded to the reaction chamber 1, and when the DC power supply is grounded, the reaction chamber 1 is also grounded.

In order to arbitrarily adjust the power supplied to the second electrode 22 and the power supplied to the first electrode 21, the output voltages of the respective DC power sources 15 and 25 should be arbitrarily adjusted.

In order to arbitrarily adjust the power supplied to the first electrode 21 and the power supplied to the second electrode, two DC power sources are used in the fifth embodiment.

However, by dividing the two outputs from one DC power supply by a voltage divider, the first and second electrodes 21 and 22 can be supplied with power and the same operation of the apparatus can be realized.

In order to equalize the state of the plasma generated in each space between the adjacent electrodes, the distances between the adjacent electrodes 21 and 22 are substantially the same, and the areas of the electrodes 21 and 22 are substantially the same. It is preferable.

In the fifth embodiment, if a film forming gas such as SiH is used, this apparatus can be used as the CVD apparatus.

If a corrosive gas such as CF is used, this device can be used as a corrosive device.

Also, if a sputtering gas such as Ar is used, this device can be used as a sputtering device.

In addition, the conditions for generating plasma are almost the same as those shown in the third and fourth embodiments.

Further, in the third to fifth embodiments, the gas pressure is preferably about 1 Pa or less, and the distance between the first and second electrodes 21 and 22 is preferably about 10 mm to 30 mm. However, if the gas pressure decreases and the average free stroke of electrons becomes long, the distance between the first and second electrodes 21 and 22 may be made larger.

As a goal for selecting the distance between the gas pressure and the adjacent electrode, it is preferable to consider that the distance between the gas pressure and the electrode is inversely proportional to each other.

In addition, when the distance between the first and second electrodes 21 and 22 is substantially the same as the diameter of the rotational movement of the electron, when the distance between adjacent electrodes becomes short, the magnetic field strength is increased to increase the diameter of the rotational movement of the electron. If the distance between electrodes is long, the magnetic field strength should be weakened to increase the diameter of the rotational motion of the electron. The magnetic field strength and the diameter of the rotational motion of the electrons are generally in inverse proportion.

Therefore, the magnetic field strength is inversely proportional to the distance between the first and second electrodes, and the magnetic field strength and the gas pressure are preferably proportional to each other.

It is preferable to apply a magnetic field of about 150 to 200gauss when the gas pressure is about 1 Pa and the distance between adjacent electrodes is about 10 to 30 mm as a target of the magnetic field strength.

11 is a graph showing the magnetic bias voltage dependence of the corrosion rate when the photoresist is corroded by zero plasma.

In FIG. 11, the line a shows the corrosion rate of the photoresist due to the magnetic bias voltage in the dry processing apparatus from the third to the fifth embodiment according to the present invention, and the line b shows the conventional magnetron. It shows the corrosion rate of the photoresist by a corrosion apparatus.

When the magnetic bias voltage is 35 V or more, the corrosion rate of the photoresist according to the third to fifth embodiments is about 40% faster than the corrosion rate of the photoresist by the conventional magnetron corrosion device.

This difference in corrosion rate means a difference in plasma density.

It is shown in the present invention that the dry corrosion treatment apparatus from the third to the fifth embodiment can generate a higher density plasma than the conventional magnetron corrosion apparatus.

In the dry processing apparatus in the third to fifth embodiments, the secondary electrons emitted from the electrodes 21 and 22 rotate the space between the first and second electrodes by the action of the magnetic field 11. In this case, the high-density plasma with good uniformity is generated.

The uniformity of this plasma is much better than that of a typical magnetron plasma.

The uniformity of the plasma is further improved by rotating the magnetic field 11 so that the magnetic field strength is equal, and the uniformity of the plasma can be accumulated by corroding the substrate 3.

When the magnetic field is fixed, when corrosion is performed by a general magnetron plasma, the in-plane distribution on the surface of the substrate 3 of the corrosion rate is around ± 35%, and the substrate is not treated with precise tolerances.

On the contrary, when the magnetic field is fixed, if the corrosion is performed by the dry processing apparatus of the third to fifth embodiments according to the present invention, the variation in the corrosion rate is ± 15%, and therefore the substrate 3 is processed with very precise tolerances.

In addition, when the magnetic field is rotated, the uniformity of the plasma is further improved with excellent corrosion uniformity of ± 3% by using the dry treatment apparatus of the third to fifth embodiments according to the present invention.

FIG. 12 is a graph showing the in-plane uniformity of the depth of corrosion when the CHF gas is introduced into the dry treatment apparatus in the fifth embodiment of the present invention to corrode a 6-inch SiO substrate, wherein the corrosion time is shown in FIG. Is about 1 minute and the magnetic field is rotated.

Since the magnetic field is rotating, the distribution of corrosion is distributed almost symmetrically with respect to the axial axis in the substrate.

The in-plane uniformity of the obtained corrosion is about ± 4%. Thus, the dry processing apparatus in the third to fifth embodiments of the present invention can generate the magnetron plasma which is more coherent than the conventional dry processing apparatus.

Since the gas pressure that can generate the magnetron discharge is lower than 1 Pa (7.5 mTorr), it is possible to form a high quality thin film with good directivity corrosion and less impurities.

In addition, since the plasma in almost the same state can be irradiated near the first and second electrodes 21 and 22, two or more substrates arranged on the respective electrodes 21 and 22 can be processed simultaneously. .

In addition, since the magnetic field is applied almost in parallel to the substrate 3, electrons in the plasma are less likely to flow toward the substrate, and thus ion seeds are hardly formed.

Therefore, since the magnetic bias voltage is less than 1/5 of the conventional dry processing apparatus, damage to the substrate due to incident ions is reduced.

For this reason, the dry treatment apparatus of the third to fifth embodiments according to the present invention has a particularly low rate of damage, a gate or trench corrosion requiring high-speed deposition, or deposition of wiring materials. It is very suitable for back.

Further, according to the present invention, the dry treatment apparatus can be miniaturized.

Claims (14)

A reaction chamber 1 having a reaction gas inlet and an outlet of exhaust gas, three or more electrodes 21 and 22 connected to the AC power supply 6 through a stop capacitor 7, and each electrode 21 and 22. Means 12 for applying one or a plurality of magnetic fields 11 for generating a magnetic field that is substantially parallel to the surface of c.), And the distance between adjacent electrodes is equal to the average free flow information of electrons in the space between adjacent electrodes. Dry treatment apparatus, characterized in that the same or set. The dry process according to claim 1, wherein the AC power supply 6 supplies synchronous AC power with appropriate phase difference through the stop capacitor 7 with the same frequency to each electrode 21,22. Device. The dry processing apparatus according to claim 1, characterized in that each electrode (21) of the first group and each electrode (22) of the second group are electrically connected to each other. The method according to claim 1, wherein the AC power supply 6 supplies AC power synchronously through the stop capacitor 7 in the same phase with the same frequency to each electrode 21, 22, and the reaction chamber 1 is grounded. Dry processing apparatus, characterized in that 2. An AC power supply according to claim 1, wherein the AC power supply is composed of a set of first AC power supply 26 and second AC power supply 16, and the dry processing apparatus further includes a first AC power supply 26 and a second AC power supply ( 16 is composed of an ideal phase 17 inserted between the first group of electrodes 21 is connected to the first AC power supply 26 through the first low storage capacitor 7, the second group of electrodes 22 Dry processing apparatus, characterized in that connected to the second alternating current power supply 16 through the second low storage capacitor (7), The dry processing apparatus according to claim 1, wherein a power divider (27) is provided in place of the stop storage battery (7). The dry processing device according to claim 6, wherein the AC power having the same frequency is supplied to the electrodes 21 and 22 synchronously through the power distribution device 27 as a suitable phase difference to the AC power source 6. . 7. The AC power supply according to claim 6, characterized in that the AC power supply 6 supplies the AC power having the same frequency to each electrode synchronously through the power distribution device 27 in the same phase and the reaction chamber 1 is grounded. Dry processing unit. The dry processing apparatus according to claim 2 or 7, wherein the phase difference is in a range of 0 ° ± 40 °. The dry processing apparatus according to claim 2 or 7, wherein the phase difference is in a range of 180 ° ± 40 °. 2. The reaction chamber (1) according to claim 1, wherein the reaction chamber (1) is connected to the anode side of the DC power supply and is grounded, and three or more electrodes (21) and (22) are connected directly to the AC power supply instead of the electrode connected to the AC power supply through the storage battery. Dry processing apparatus characterized in that connected to the negative side of the power supply. 12. The method of claim 1 or 6 or 11, wherein the distance between adjacent electrodes 21 and 22 is 1-5 cm and the reaction chamber 1 is evacuated to a pressure of 0.13-13 Pa or less and is about 0.5x. Dry processing apparatus characterized in that a current flows through the magnetic field applying means (12) to generate a magnetic field of 10² -5 × 10². The method of claim 1, wherein the distance between adjacent electrodes 21, 22 is 10-30 mm, the pressure in the reaction chamber 1 is about 1.3 Pa or less, and about 1.5 ×. Dry processing apparatus, characterized in that a current that can generate a magnetic field of 10²-2.0 × 10² through the magnetic field applying means (12). 12. The dry type according to claim 1, 6, or 11, wherein each electrode (21) (22) has the same area, and the respective distances between adjacent electrodes (21) (22) are the same. Processing unit.